Azo compounds containing dihydroxyphenyl groups and oxalyl ester groups



United States Patent ABSTRACT OF THE DISCLOSURE The present invention is directed to azo and anthraquinone dyes containing at least one and not more than two groups selected from the group consisting of alkoxalyl and aryloxalyl esters of aliphatic hydroxyl groups, said dyes further containing at least one and not more than two groups selected from the group consisting of orthoand para-dihydroxyphenyl groups.

This application is a continuation of our copending U.S. application Ser. No. 813,702, filed May 18, 1959, now abandoned, which, in turn, is a continuation-in-part of our copending U.S. application Ser. No. 697,809, filed Nov. 21, 1957 (now abandoned).

This invention relates to photography and more particularly to products and processes for the development of photosensitive silver halide elements.

It is a primary object of the present invention to provide novel diffusion-transfer photographic processes and products whereby improved control of the transfer of mobile dye developer to an image-receiving layer may be obtained.

A further object of the present invention is to provide novel photographic processe and products for obtaining color images by a diffusion-transfer process wherein a dye developer is initially present in the form of a hydrolyzable dye developer and wherein said hydrolyzable dye developer is subjected to hydrolysis during processing.

A still further object of the present invention is to provide novel photographic processes and products wherein a hydrolyzable dye developer is employed and said dye developer is of relatively low mobility until hydrolysis occurs.

A still further object of the present invention is to provide photographic processes and product for use in monochromatic and multicolor diffusion-transfer processes utilizing hydrolyzable dye developers, which dye developers contain groups removable during photographic processing, to provide thereby improved color rendition.

A still further object of the present invention is to provide novel processes for the development of silver halide emulsions, in which the novel developing agent is capable of developing a latent image and imparting a positive colored image of said latent image to a superposed imagereceiving layer.

A still further object of the present invention is to provide novel photographic processes and products for obtaining color images by diffusion-transfer processes which employ hydrolyzable dye developers, which dye developers comprise the hydrolyzable alkoxalyl and aryloxalyl esters of specified dye developers.

Other objects of the invention will be in part be obvious and will in part appear hereinafter.

'The invention accordingly comprises the several steps and the relation and order of one or more of such steps with respect to each of the ohers, and the product possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description.

The compounds employed in the present invention possess the properties of both a dye and a developing agent; thus they may be referred to as dye developers. The nature of these dye developers will be described hereinafter.

The photographic processes and compositions disclosed herein are particularly useful in the treatment of a latent image present in a photosensitive element, such as an exposed silver halide emulsion, whereby a positive dye image thereof may be imparted to another element, herein referred to as an image-carrying or image-receiving element.

The copending application of Howard G. Rogers, Ser. No. 748,421, filed July 14, 1958, a continuation-in-part of Ser. No. 415,073, filed Mar. 9, 1954 (now abandoned), discloses diffusion-transfer reversal processes wherein a photographic negative material such as a photographic element comprising an exposed silver halide emulsion layer containing a latent image, is processed to impart to an image-receiving element a reversed or positive dye image of said latent image by permeating into said emulsion layer a suitable liquid processing composition and bringing said emulsion layer into superposed relationship with an appropriate image-recei1ving layer. It is an object of this invention to provide additional compounds suitable for use in such processes.

In carrying out the process of this invention, a photosensitive element containing a silver halide emulsion is exposed and wetted with a liquid processing composition, for example, by immersing, coating, spraying, flowing, etc., in the dark, and the photosensitive element superposed, prior to, during or after wetting, on a sheetlike support element, which may be utilized as an imagereceiving element. In a preferred embodiment, the photosensitive elernent contains a layer of hydrolyzable dye developer, and the liquid processing composition is applied to the photosensitive element in a uniform layer as the photosensitive element is brought into superposed position with an image-receiving element. It is also within the scope of this invention to apply the liquid processing composition prior to exposure, in accordance with the disclosure in the copending application of Edwin H. Land, Ser. No. 498,672, filed Apr. 1, 1955, and now U.S. Patent No. 3,087,816. The liquid processing composition permeates the emulsion to provide a solution of dye developer substantially uniformly distributed therein. As the latent image is developed, the oxidation product of the dye developer is immobilized or precipitated in situ with the developed silver, thereby providing an imagewise distribution of unoxidized dye developer dissolved in the liquid processing composition. This immobilization is apparently, at least in part, due to a change in the solubility characteristics of the dye developer upon oxidation, and especially as regards its solubility in alkaline solutions. It may also be due, in part, to a tanning effect on the emulsion by the oxidized developing agent and to localized exhaustion of alkali due to development. At least part of this imagewise distribution of unoxidized dye developer is transferred, by imbibition, to a superposed image-receiving layer or element, said transfer substantially excluding silver or oxidized dye developer. Under certain circumstances, the layer of the liquid processing composition may be utilized as the image-receiving layer. The latter element receives a depthwise diffusion, from the emulsion, of unoxidized dye developer without appreciably disturbing the imagewise distribution thereof to provide a reversed or positive, colored image of the developed image. The image-receiving element may contain agents adapted to mordant or otherwise fix the diffused, unoxidized dye developer. If the color of the diffused dye developer is affected by changes in the pH of the image-receiving element, this pH may be adjusted in accordance with well-known techniques to provide a pH affording the desired color. Imbibition periods of approximately one minute have been found to give good results, but this contact period may be adjusted where necessary to compensate for variations in temperature or other conditions. The desired positive image is revealed by stripping the image-receiving element from the photosensitive element at the end of the imbibition period.

The compounds of the present invention may be utilized in the photosensitive element, for example in, on or behind the silver halide emulsion, or they may be utilized in the image-receiving element. In a preferred embodiment, a coating or layer of the compound is placed behind the silver halide emulsion, i.e., on the side of the emulsion adapted to be located most distant from the photographed subject when the emulsion is exposed and preferably also adapted to be most distant from the image-receiving element when in superposed relationship therewith. Placing the hydrolyzable dye developer behind the emulsion layer, as in the preferred embodiment, has the advantage of providing increased contrast in the positive image, and also minimizes any light-filtering action by the colored dye developer. In this preferred embodiment, the layer of hydrolyzable dye developer may be applied by using a coating solution so selected as not to induce hydrolysis during preparation of the negative and containing about 0.5 to 8% by weight, of the dye developer.

The liquid processing composition above referred to comprises at least an aqueous solution of an alkaline compound, for example, diethylamine, sodium hydroxide or sodium carbonate. In some instances, it may contain an auxiliary or accelerating developing agent. If the liquid processing composition is to be applied to the emulsion by being spread thereon, preferably in a relatively thin, uniform layer, it may also include a viscosity-increasing compound comprising a film-forming material of the type which, when said composition is spread and dried, will form a relatively firm and relatively stable film. A preferred film-forming material is a high molecular weight polymer such as a polymeric, water-soluble ether inert to an alkali solution, as for example, a hydroxyethyl cellulose or sodium carboxymethyl cellulose. Other filmforming materials or thickening agents whose ability to increase viscosity is substantially unaffected when left in solution for a long period of time may also be used.

The copending application of Edwin H. Land and Howard G. Rogers, Ser. No. 669,542, filed July 2, 1957, and now abandoned, discloses diffusion-transfer processes of the previously disclosed type which employ hydrolyzable dye developers. These hydrolyzable dye developers are disclosed to be initially less mobile and thus prevent premature transfer of dye developer which might give rise to highlight stain .and/ or incomplete color separation. The present application is principally concerned with novel hydrolyzable dye developers particularly applicable for use in the processes therein disclosed.

The dye developers of the present invention comprise dyes, preferably azo, anthraquinone, indophenol, indoaniline, and azomethine dyes, most preferably azo or anthraquinone dyes, characterized in that they contain not less than one and preferably not more than two groups selected from the group consisting of the alkoxalyl and aryloxalyl esters of aliphatic hydroxyl groups, said dyes being further characterized in that they contain not less than one and preferably not more than two groups selected from the group consisting of orthoand para-dihydroxyphenyl groups.

The preferred novel hydrolyzable dye developers of the present invention comprise azo, anthraquinone, indophenol, indoaniline, and azomethine dye developers characterized in that they contain not less than one and n more than two groups within the formula:

m R-o-o-oo :a )..o1 wherein R is an alkylene group, preferably a lower alkylene group comprising from 1 to 5 carbon atoms, for'example, ethylene, trimethylene, propylene r (-CHCH2) etc.; R is an alkylene group comprising not less than two and not more than four carbon atoms, such as, for example, ethylene, trimethylene, propylene, etc.;, n is 0 or an integer from 1 to 3, inclusive; and R is an alkyl or aryl group; said dye being further characterized in that it contains not less than one and not more than two groups selected from the group consisting of o-dihydroxyphenyl and p-dihydroxyphenyl groups.

As illustrations of suitable alkyl groups signified by the term R in Formula A, mention may be made of: ethyl, butyl hexyl, lauryl, etc. In general, the alkyl group preferably contains from 1 to 12 carbon atoms where n is 0 and from 1 to 4 carbon atoms where n is a positive integer from 1 to 3, inclusive.

As examples of suitable aryl groups contemplated by R mention may be made of phenyl and substituted phenyl groups, e.-g., tolyl, etc.

The respective o-dihydroxyphenyl and p-dihydroxyphenyl group or groups may be linked to the chromophore-containing component of the dye molecule by utilization of a divalent radical or a covalent bond. As examples of divalent radicals, suitable for use in the practice of the present invention, mention may be made of: divalent organic radicals such as alkylene radicals, preferably lower alkylene radicals such as ethylene, isopropylene, etc.; sulfonamido; sulfamyl; carboxamido; carbamyl; arylene radicals such as phenylene, etc.; aralkylene radicals such as phenethyl, etc.; acyl radicals such as It alkylene-C etc.; and divalent radicals which contain more hetero and carbon atoms as constituent components, as for example,

In a preferred embodiment of Formula A, R is an ethylene group and the preferred dyes may be characterized in that they contain a single alkylene linked unsubstituted p-dihydroxyphenyl group. Such compounds may be represented by the formula:

1 wherein M is an alkylene group; p is 1 or 2; R n and R have the same significance as noted in Formula A; and 1) represents a dye radical, preferably an azo or anthraquinone dye radical.

The term dihydroxyphenyl as used herein is intended to include the nuclear substituted derivatives thereof, especially the nuclear substituted alkyl and halogen derivatives thereof. Where derived, the phenyl nucleus may be substituted by additional substituents, that is, radicals so situated as not to impair the respective silver halide developing function of the dihydroxy substituted phenyl group.

While the preferred compounds of the present invention have been described above as containing a delimited number of recurring ether groups, that is 1 to 4 ether groups, it is to be understood that polyether groups of greater magnitude may be employed, where desired, in accordance with the requirements of the operator.

The novel dyes of the present invention may be prepared by reacting a dye developer, preferably an azo, anthraquinone, indophenol, indoaniline, or azomethine dye developer, having not less than one and preferably not more than two aliphatic hydroxyl groups with an alkyl and/or an aryl oxalyl halide such as an alkoxalyl or aryloxalyl bromide or chloride, preferably an alkoxalyl or aryloxalyl chloride. Where the dye developer has additional available reactive hydroxyl groups, reaction may occur at such additional groups.

The compounds of Formula A may be prepared by reacting a dye, preferably an azo, anthraquinone, indophenol, indoaniline, or azomethine dye, characterized in that it contains not less than one and preferably not more than two aliphatic hydroxyl groups and said dye is further characterized in that it contains not less than one and not more than two groups selected from the group consisting of o-dihydroxyphenyl and p-dihydroxyphenyl groups and halogen and alkyl derivatives thereof; with a compound selected from those represented by the formula:

wherein R R and n have the same significance as noted in Formula A and W is a halogen radical, preferably a chlorine radical; preferably in a reaction medium comprising a suitable anhydrous halogen acid acceptor, e.g., quinoline, pyridine, etc. The reaction is preferably performed on a steam bath, but it is within the scope of this invention also to employ temperatures that vary from below room temperature to above 100 C. The particular conditions employed will vary according to the oxalyl halide and the halogen acid acceptor employed. It will be understood that the aforementioned dye may contain additional unreacted hydroxyl groups as constituent components of an aromatic system.

The preparations of numerous of the dye developers preferred for use in synthesizing the hydrolyzable dye developers of the present invention are set forth in the following copending US. applications.

Ser. No. 445,171, filed July 22, 1954, in the name of Richard S. Corley, now abandoned, the subject matter of which has been incorporated in Ser. Nos. 849,726 and 849,648, both of which are now abandoned. The above original application, inter alia, disclosed compounds of the formula:

wherein: R is selected from the group consisting of hydrogen and alkyl radicals; Y is the residue of a dye molecule i YNH 6 X is selected from the group consisting of I Z--N; N-Y sulfo, hydroxyl, alkyl, amino, and alkyl-amino radicals; and Z represents a radical possessing a silver halide developing agent;

Ser. No. 449,514, filed Aug. 12, 1954, in the names of Elkan R. Blout and Myron S. Simon, now abandoned, the subject matter of which has been incorporated in Ser. No. 849,727, filed on Oct. 30, 1959. The above application inter alia disclosed a novel class of dye developers of the formula:

Y o X I II I I I I X 0 1 IX wherein: Y is a radical possessing a silver halide developing function; R is selected from the group consisting of hydrogen and alkyl radicals; each X is selected from the group consisting of hydrogen, hydroxyl, amino, alkyl, sulfo, alkoxy, aryloxy, alkylamino and arylamino radicals; and each Z is selected from the group consisting of hydrogen, amino, alkyl, aryl, alkoxy, aryloxy, hydroxyl, carboxyl, and sulfo radicals and salts thereof;

Ser. No. 471,542, filed Nov. 26, 1954, in the names of Elkan R. Blout, Saul G. Cohen, Milton Green, Howard G. Rogers, Myron S. Simon, and Robert B. Woodward, now abandoned, the subject matter of which had been incorporated in Ser. No. 1,442 and Ser. No. 1,443, both filed Jan. 11, 1960, and both abandoned, the subject matter of the latter of which has been incorporated in Ser. No. 401,714, filed Oct. 5, 1964, now Patent No. 3,288,778. The above original application was concerned with, inter alia, novel azo and anthraquinone dyes of the formula:

R0 II R is selected from the group consisting of hydrogen and alkyl radicals; n is selected from the group consisting of 0 and integers from 1 to 5; and Z is selected from the group consisting of benzene nuclei substituted in the ortho and para positions with respect to each other by members of the group consisting of hydroxyl and amino radicals;

Ser. No. 473,458, filed Dec. 6, 1954, in the names of Elkan R. Blout, Saul G. Cohen, Milton Green, and Myron S. Simon, and now US. Patent No. 3,077,402;

Ser. No. 478,922, filed Dec. 30, 1954, in the names of Elkan R. Blout, Marilyn R. Cohler, Milton Green, Myron S. Simon and Robert B. Woodward, now abandoned, the subject matter of which has been incorporated in Ser. No. 824,785 and Ser. No. 824,786, both filed July 3, 1959, in turn now abandoned, the subject matter which has been incorporated in respectively, Ser. No. 233,461, filed Oct. 26, 1962, now US. Patent No. 3,135,606, and Ser. No. 318,827, now US. Patent No. 3,209,016. The above original application disclosed and claimed, inter alia,

novel anthraquinone dyes of the formula:

Y A(NHZX) wherein: A is an anthraquinone dye radical; X is a radical possessing a silver halide developing function and preferably contains a benzene or naphthalene nucleus; Z is a bivalent organic radical containing at least one methylene (CH group; each Y may be a hydrogen, amino, alkyl, aryl, halogen, alkylamino, arylamino, alkoxy, aryloxy, hydroxyl, sulfonamido, carboxamide, nitrocarboxyl, or sulfo radical; and m is a positive integer less than 5;

Ser. No. 485,342, filed Jan. 31, 1955, in the name of Richard S. Corley, now U.S. Patent No. 2,983,605. The instant patent is directed to, inter alia, photographic processing compositions containing anthraquinone dyes similar to those described in the paragraph next above;

Ser. No. 485, 840, filed Feb. 3, 1955, in the names of Elkan R. Blout and Howard G. Rogers, now U.S. Patent No. 3,255,001. The instant patent is directed to, inter alia, photographic compositions containing dye developers which comprise a dye moiety linked to a silver halide developing moiety by an achromophoric bond which acts to interrupt any system of conjugation or resonance extending from the dye unit to the developer unit;

Ser. No. 521,874, filed July 13, 1955, in the names of Elkan R. Blout, Milton Green, Myron S. Simon, and Howard G. Rogers (now abandoned and replaced by Ser. No. 799,427, filed Mar. 16, 1959, now U.S. Patent No. 3,076,820. The original application was drawn to, inter alia, dye developers of the formula:

wherein: A represents an anthraquinone group; Z is a bivalent organic group; alk represents a lower alkylene group; n is selected from the group consisting of 0 and 1; m is an integer between 1 and 4, inclusive; p is selected from the group consisting of 0 and m; and X represents an organic group which possesses substituents imparting thereto a silver halide developing function;

Ser. No. 522,848, filed July 18, 1955, in the names of Elkan R. Blout, Sydney Kasman and Myron S. Simon (now abandoned and replaced by Ser. No. 799,425, filed Mar. 16, 1959, in turn abandoned, the subject matter of which has been incorporated in Ser. No. 150,661, filed Nov. 7, 1961, now U.S. Patent No. 3,076,808. The original application was drawn to and claimed, inter alia, dye developers which contain an anthrapyridine, that is, 3- azabenzanthrone nucleus to which is attached an organic group capable of functioning as a silver halide developing p;

Ser. No. 612,045, filed Sept. 25, 1956, in the names of Elkan R. Blout, Milton Green and Howard G. Rogers, now abandoned, the subject matter of which has been incorporated in Ser. No. 144,816, filed Oct. 18, 1961, now U.S. Patent No. 3,134,672. The original application was drawn to, inter alia, novel azo dyes of the formula:

wherein: R is an alkylene group, preferably an alkylene group containing no more than five carbons and more preferably an ethylene group; Ar is an aryl nucleus such as a benzene or naphthalene nucleus; each Z is an alkyl group, preferably a lower alkyl group such as methyl or ethyl or a halogen such as chlorine; n is 0, 1 or 2; Y is a 2,5-dihydroxy, a 2,3-dihydroxy or a 3,4-dihydroxy phenyl group which also may be substituted by alkyl or halogen groups; In is 1 or 2; and X is the radical of an azo coupling component;

Ser. No. 612,052, filed Sept. 25, 1956, in the names of Milton Green and Howard G. Rogers, now abandoned, the subject matter of which has been incorporated in Ser. No. 165,930, filed Jan. 12, 1962, now U.S. Patcut No. 3,135,604. The original application was drawn to, inter alia, azo dyes of the formula:

R2 wherein M is selected from the group consisting of YR -Arand groups; Ar is an aryl nucleus selected from the group consisting of benzene and naphthalene nuclei, said N=N-- group being directly attached to a ring carbon of said aryl nucleus; each Z is selected from the group consisting of halogen and lower alkyl groups; each Z is selected from the group consisting of lower alkyl, halogen and lower alkoxy groups; m is an integer from 0 to 2, inclusive; Y is selected from the group consisting of p-dihydroxyphenyl, o-dihydroxyphenyl radicals and alkyl and halogen substituted p-dihydroxyphenyl and o-dihydroxyphenyl radicals; R is a divalent alkylene group containing no more than five carbon atoms and directly attached to said aryl nucleus Ar and to said phenyl ring of Y; Q is a divalent radical of an azo dye coupler linked to said N=N- group and to said group and completing said azo dye developer; R is selected from the group consisting of hydrogen and lower alkyl groups; n is an integer from 0 to 5, inclusive; and X is a benzene nucleus substituted in the ortho and para positions with respect to each other by members of the group consisting of hydroxyl and amino radicals;

Ser. No. 612,053, filed Sept. 25, 1956, in the name of Myron S. Simon, now abandoned, the subject matter of which has been incorporated in Ser. No. 196,523, filed May 21, 1962, now U.S. Patent No. 3,183,089, and Ser. No. 196,524, filed May 21, 1962, now U.S. Patent No. 3,'134,7 65. The original application, was concerned with, inter alia, azo dyes of the formula:

wherein: Y is selected from the group consisting of 2,5-dihydroxy, 2,3-dihydroxy and 3,4-dihydr'oxyphenyl radicals and alkyl and halogen substituted derivatives thereof; Ar is an aryl nucleus; each Z is selected from the group consisting of halogen, alkoxy and alkyl groups; n is selected from the group consisting of 0, 1 and 2; X is the residue of a coupling component and m is an integer selected from the group consisting of 1 and 2;

Ser. No. 612,054, filed Sept. 25, 1956, in .the names of Helen P. Husek and Myron 8. Simon, now abandoned, the subject matter of which has been incorporated in Ser. No. 197,259, filed May 24, 1962, now U.S. Patent No. 3,134,763, and Ser. No. 197,283, filed May 24, 1962, now Patent No. 3,236,645. The original application was directed to, interalia, novel dyes of the formula:

wherein: Ar isan aryl nucleus; each Z is selected from the group consisting of halogen, alkyl and alkoxy groups; n is selected from the group consisting of 0, 1 and 2; Y is selected from the group consisting of 2,5-dihydroxyphenyl, 3,4-dihydr'oxyphenyl, 2,3-dihydroxyphenyl groups and halogen and alkyl substituted derivatives thereof; m is selected from the group consisting of 1 and 2; and

9 X and X each represent the residues of coupling components;

Ser. No. 612,055, filed Sept. 25, 1956, in the name of Helen P. Husek, now abandoned, the subject matter of which has been incorporated in Ser. No. 192,354, filed May 4, 1962, 'now U.S. Patent No. 3,134,762, and Ser. No. 192,355, filed May 4, 1962, now U.S. Patent No. 3,236,643. The original application was directed to, inter alia, dyes of the formula:

wherein: R is an alkylene group; Ar is an aryl nucleus; each Z is selected from the group consisting of halogen and alkyl groups; n is selected from the group consisting of 0, l and 2; Y is selected from the group consisting of 2,5-dihydroxyphenyl, 3,4-dihydroxyphenyl, 2,3-dihydroxyphenyl groups and halogen and alkyl substituted derivatives thereof; m is selected from the group consisting of 1 and 2; and X and X each represents a residue of a coupling component;

Serial No. 663,905, 'filed June 6, 1957, in the names of Milton Green and Howard G. Rogers, now abandoned, the subject matter of which has been incorporated in Ser. No. 193,293, filed May 8, 1962, now U.S. Patent No.'3,173,906, and Ser. No. 193,326, filed May 8, 1962, now U.S. Patent 'No. 3,222,169. The original application was directed to, interalia, monoazo and diazo dyes represented by the formulae:

wherein: X is selected from the group consisting of a radical of an azo dye coupler linked to said -N=N- group, a

radical; Y is a member selected from the group consisting of a 2,5-dihydroxyphenyl group and alkyl and halogen nucleus substituted 2,5-dihydroxyphenyl groups; R is an alkylene group containing not more than five carbon atoms; each Z is selected from the group consisting of lower alkyl and halogen groups; each Z is selected from the group consisting of lower alkyl, alkoxy andn halogen groups; n is an integer from to 2, inclusive; Ar is an aryl nucleus selected from thev group consisting of benzene and naphthalene nuclei; m is an integer from 0 to 1, inclusive; X is a radical of an azo dye coupler linked to said N=N group; said X and X radicals completing said azo dye;

Ser. No. 669,969, filed July 5, 1957, in the name of Milton Green, now abandoned. This application was directed to, inter alia dyes represented by the formula:

wherein: Y is a p-dih ydroxyphenyl silver halide developing radical; R is an alkylene group comprising not more than five carbon atoms; and NHX is an azo dye radical of the azo dye NH -X;

Ser. No. 678,439, filed Aug. 15, 1957, in the name of Myron S. Simon, now abandoned, the subject matter of which has been incorporated in Ser. No. 232,584, filed Oct. 23, 1962, now U.S. Patent No. 3,131,061, and Ser. No. 232,585, filed Oct. 23, 1962, now U.S. Patent No. 3,255,206. The original application dealt with, inter alia,

10 novel class of anthraquinone dye developers which may be utilized in forming the hydrolyzed dyes of the present invention;

Ser. No. 689,403, filed Aug. 26, 1957, in the name of Milton Green, now abandoned, the subject matter of which has been incorporated in Ser. No. 316,498, filed Oct. 16, 1963, now abandoned. The original aplpication dealt with, inter alia, novel dyes represented by the formula:

wherein: Ar is an aryl nucleus; each Z is selected from the group consisting of halogen and alkyl groups; m is selected from the group consisting of 0 and 1; n is selected from the group consisting of O, 1 and 2; p is selected from the group consisting of 1 and 2; Y is selected from the group consisting of benzene nuclei substituted in the ortho and para position with respect to each other by hydroxyl radicals and alkyl and halogen substituted derivatives thereof; and X and X each represents a residue of an azo coupling component;

Ser. No. 680,434, filed Aug. 26, 1957, in the name of Milton Green, now abandoned, the subject matter of which has been incorporated in Ser. No. 230,287, filed Oct. 12, 1962, now U.S. Patent No. 3,230,086, and Ser. No. 230,288, filed Oct. 12, 1962, now U.S. Patent No. 3,218,312. The original application was directed to, inter alia, novel dyes represented by the formula:

wherein: Ar is an aryl nucleus; each Z is selected from the group consisting of halogen, alkyl and alkoxy groups, m is selected from the group consisting of 0 and 1; u is selected from the group consisting of 0, 1, 2 and 3; v is selected from the group consisting of 0, 1 and 2; p is selected from the group consisting of 1 and 2; Y is selected from the group consisting of p-dihydroxyphenyl and p-bisacyloxyphenyl groups; and X and X, each represents a residue of an azo coupling component;

Ser. No. 680,437, filed Aug. 26, 1957, in the names of Elkan R. Blout and Myron S. Simon, now U.S. Patent No. 3,047,386. The instant patent is directed to, inter alia, novel anthraquinone dye developers;

Ser. No. 680,619, filed Aug. 27, 1957, in the names of Elkan R. Blout and Myron S. Simon, now abandoned;

Ser. No. 685,081, filed Sept. 20, 1957, in the names of Elkan R. Blout, Milton Green, Howard G. Rogers, and Myron S. Simon, now abandoned, the subject matter of which has been incorporated in Ser. No. 225,656, filed Sept. 10, 1962, now US. Patent No. 3,142,565, and Ser. No. 222,702, filed Sept. 10, 1962, now U.S. Patent No. 3,208,991. The original application was drawn to, inter alia, novel azo dyes of the formula:

wherein: Ar is an aryl nucleus; each Z is selected from the group consisting of hydroxyl, halogen, alkyl and alkoxy groups; m is selected from the group consisting of 0 and 1; n is selected from the group consisting of 0 and the positive integers from 1 to 4, inclusive; p is selected from the group consisting of '1 and 2; R is an alkylene group; Y is selected from the group consisting of p-hydroxyphenyl and o-dihydroxyphenyl groups and alkyl and halogen substituted derivatives thereof; and X and X each represents a ersidue of a coupling component;

Ser. No. 703,515, filed Dec. 18, 1957, in the name of Milton Green, now abandoned;

1 1 'Ser. No. 707,109, filed Jan. 6, 1958, in the names of Elkan R. Blout, Milton Green, Howard G. Rogers and Robert B. Woodward, now abandoned. This application was directed to, inter alia, novel dyes of the formula:

wherein: Z is a dihydroxyphenyl silver halide developing radical; Y is selected from the group consisting of alkylene and alkarylene radicals; p is a positive integer from 1 to 2; and SO -],,X represents a radical of a dye selected from the group consisting of mono and disulf-onyl substituted azo and anthraquinone dyes having a substituent displaced from each sulfonyl group by the group Ser. No. 709,001, filed Jan. 15, 1958, in the names of Milton Green, Helen P. Husek and Sydney Kasman, now abandoned, the subject matter of which has been incorporated in Ser. No. 200,639, filed June 7, 1962, now U.S. Patent No. 3,214,469;

Ser. No. 709,002, filed Ian. 15, 1958, in the names of Milton Green and Helen P. Husek, now abandoned, the subject matter of which has been incorporated in Ser. No. 75,128, filed Dec. 12, 1960, now U.S. Patent No. 3,158,595. The original application was concerned with, inter alia, certain dye developers within the formula:

wherein: Z is a benzene nucleus substituted by hydroxyl groups in the ortho or para position with respect to each other and halogen substituted derivatives thereof; n is or a positive integer from 1 to 5; and

i NX represents the residue of a dye molecule F HN-X wherein: X represents the dye molecule other than the reactive amino group; annd R is hydrogen or an alkyl group;

Ser. No. 709,005, filed Jan. 15, 1958, in the names of Sydney Kasman and Helen P. Husek, now abandoned, the subject matter of which has been incorporated in Ser. No. 75,127, filed Dec. 12, 1960, in turn abandoned, the subject matter of which has been incorporated in Ser. No. 339,615, filed Jan. 23, 1964;

Ser. No. 711,811, filed Jan. 29,1958, in the name of Milton Green, now abandoned, the subject matter of which has been incorporated in Ser. No. 232,613, filed Oct. 23, 1962, now U.S. Patent No. 3,246,985. The

12 original application was directed to, interalia,'dyes represented by the formula:

' CH2(HJI'IIT-X 0 R X-1TI(|IJCH wherein: each R is selected from the group consisting of hydrogen, alkyl and aryl groups and the radical is the residue of a dye molecule having at least one substituent selected from the group consisting of reactive primary and secondary amino groups;

Ser. No. 748,145, filed July 14, 1958, in the names of Milton Green and Howard G. Rogers, now abandoned, the subject matter of which has been incorporated in Ser. No. 190,804, filed Apr. 27, -1962, now U.S. Patent No. 3,186,982;

Ser. No. 755,804, filed Aug. 18, 1958, in the names of Elkan R. Blout, Saul G. Cohen, Milton Green and Myron S. Simon, now abandoned. That application was drawn to, inter alia, dyes, as, for example, phenylazo hydroquinone, 2-azohydroquinone-l-naphthol, etc.;

Ser. No. 771,719, filed Nov. 4, 1958, in the names of Myron 8. Simon, now abandoned. That application was drawn to dye developers such as, for example, -N-2,5-dihydroxybenzylidene-p-phenylazoaniline, etc.;

Ser. No. 711,719, filed Nov. 4, 1958, in the names of Elkan R. Blout and Richard S. Corley, now abandoned, the subject matter of which has been incorporated in Ser. No. 193,320, filed May 8, 1962, now U.S. Patent No. 3,236,864. The original application defines, inter alia, novel azo and anthraquinone dyes which may be utilized in the instant invention to form the novel bydrolyzable dye developers, disclosed herein; and

Ser. No. 788,893, filed Jan. 26, 1959, in the names of Milton Green and Myron S. Simon, now abandoned, the subject matter of which has been incorporated in Ser. No. 359,998, filed Apr. 15, 1964, now U.S. Patent No. 3,299,041. As in many of the instances above, the original application is directed to, inter alia, monoazo and diazo dyes which may be utilized in the environment of the present invention.

A preferred compound within the scope of this invention comprises 4- [p- (2,5'-dihydroxyphenethyl) phenylazo] -3- [N- (B-hexoxalyloxyethyl) carboxamido] -1-pheny1-5-pyrazolone As examples of further compounds within the scope of this invention mention may be made of:

OH OH i u n O O 2-[p- (2,5-dihydroxyphenethyl) phenylazo] -4-(flethoxalyloxyethoxy -1-naphth0l 4- [p 2,5-dihydroxyphenethyl) -phenylazo] -3-[N- (fl-lauroxalyloxyethyl) -carboxamido] -1-pheny1-5-pyrazolone butoxyethoxyethoxalyloxyethoxy-2- [p- (2 ,5 -dihydroxyph enethyl) -pheny1azo] l-n aphthol 3-[N-(butoxyethoxyethoxalyloxyethyl)-carh0xamid0] 4 [p (2,5-dihydroxypheuethyl) phenylazo] 1 pheny1-5-py- 4- [B- 2' ,5-dihyrdoxyphenyl) -a-methy1-ethy1amino] -1- ethXalyloxyethylamlnoanthraquinone 4- [p- (2',5-dihydroxyphenethyl) -pheny1azo] -3- [N- (fi-octaoxalyloxyethyl) -carboxamtdo] -l-pheny1-5-pyrazo1one 2 [p- (2',5'-dihydroxy-4-methyl-phenethyl) -pheny1azo] -4- (fi-ethoxalyloxyethoxy) -l-naphth0l The invention will be illustrated in greater detail in conjunction with the following specific examples which set out representative preparations and photographic utilization of the novel compounds of this invention, which, however, are not limited to the details therein set forth and are intended to be illustrative only.

EXAMPLE 1 To prepare 4-[p (2',5 dihydroxyphenethyl)-phenylazo] 3 [N 8 lauroxalyloxyethyl)-carboxamido]-1- phenyl-S-pyrazolone, 20 g. of 3-carbethoXy-1-phenyl-5- pyrazolone are dissolved in 200 cc. of ethanolamine and the solution refluxed for 16 hours. The excess ethanolamine is then removed in vacuo, the residue dissolved in cc. of ethanol and the resultant solution poured into a liter of dilute hydrochloric acod. The solid product, 3-[N- (fl-hydroxyethyl -carboxamido] -1-phenyl-5-pyrazolone, is filtered, crystallized from aqueous ethanol and exhibits a melting point at C.

Analysis for nitrogen:

2,5-bis-acetoxy-phenethyl-aniline, prepared according to the procedure disclosed in the copending US. application of Milton Green and Helen P. Husek, Ser. No. 612,063, filed Sept. 25, 1956 (now abandoned and replaced by Ser. No. 805,673, filed Apr. 13, 1959, and now US. Patent No. 3,019,254), is diazotized by adding (0.01 mol) thereof to 20 cc. of water, 16 cc. of concentrated hydrochloric acid, and treating at approximately 5 C. with 0.7 g. of sodium nitrile dissolved in 10 cc. of water.

The diazo product is added, dropwise with stirring, to a solution of (0.01 mol) of 3-[N-(B-hydroxyethyD-carboxamido]-1-phenyl-5-pyrazolone in 50 cc. of water, 4.2 g. of sodium carbonate and 10 cc. of ethanol, the solution having previously been cooled to approximatel 5 C. The resulting yellow precipitate is filtered and then treated, under nitrogen, with 25 cc. of ethanol and 25 cc. of a 20% sodium hydroxide solution for five minutes at 90 to 100 C. Acidification of the resulting solution with dilute hydrochloric acid and recrystallization from ethanol yields 4- [p (2,5 dihydroxyphenethyl) phenylazo] 3 [N- (,8 hydroxyethyl) carboxa-mido]-1-phenyl-5-pyrazolome melting at 246 to 248 C. The product is soluble in organic solvents such as acetone and ethanol, resulting in a yellow solution. The absorption spectrum of this compound in ethanol exhibits 21 A at 450 m e=26,300.

1.5 g. of the above yellow dye developer are dissolved in 100 cc. of dry pyridine and 2.5 g. of lauroxalyl chloride are added. The solution is warmed on a steam bath for two hours, taking care to exclude moisture, and then poured into a solution of ice and dilute hydrochloric acid. The solid residue which separated is warmed with 50 cc. of absolute ethanol, chilled approximately 12 hours and a small amount of the starting material which had precipitated is removed by filtration. The filtrate is evaporated to dryness, the residue triturated with benzeneand then filtered. The resultant product is a solid, 4-[p (2',5'- dihydroxyphenethyl) phenylazo] 3 [N (,8 lauroxalyloxyethyl -carboxamido] l-phenyl-S-pyrazolone.

Analysis for nitrogen:

Percent Calculated 9.8 Found 9.8

EXAMPLE 2 To prepare 4-[p-'(2',5' dihydroxyphenethyl) phenylazo] 3 [N-(B-hexoxalyloxyethyl) carboxamido1-lphenyl-S-pyrazolone, 1.5 g. of 4-[p-(2',5'-dihydroxyphenethyl)-phenylazo] 3 [N ([3 hydroxyethyD-carboxamido]-1-phenyl-5-pyrazolone, prepared according to the procedure disclosed in Example 1, are dissolved in 100 cc. of anhydrous pyridine, 2.5 g. of hexoxalyl chloride are added to the solution and the esterification is conducted under conditions substantially similar to those disclosed in Example 1. The resultant product is a yellow solid, 4-[p- (2',5'-dihydroxyphenethyl)-phenylazo] 3 [N-(fi-hexoxalyloxyethyl) -carboxamido] -1-phenyl-5-pyrazolone.

EXAMPLE 3 To prepare 3-[N-(butoxyethoxyethoxalyloxyethyl)carboxamido]-4-[p-(2,5-dihydroxyphenethyl) phenylazo]- l-phenyl-S-pyrazolone, 2 g. (0.004 mol) of 4-[p-(2',5'-dihydroxyphenethyl)-phenylazo]-3- [N (B hydroxyethyl)- carboxamido]1phenyl-5pyrazolone, prepared according to the procedure disclosed in Example 1, are dissolved in 30 cc. of anhydrous pyridine. 2.1 g. (.006 mol) of butoxyethoxyethoxalyl chloride are added to the solution, the mixture is warmed in vacuo on a steam bath for 3 hours and let stand at room temperature for approximately 12 hours. The solution is then mixed with a dilute hydrochloric acid solution and the resulting granular slurry filtered. The filter cake is washed with water and dried by concentrating several times, under vacuum, a benzene slurry of the filter cake. The resultant residual gum is washed several times by slurry with benzene and extracted with chloroform. The desired product is obtained by evaporation of the chloroform solution to dryness.

EXAMPLE 4 To prepare 4-butoxyethoxyethoxalyloxyethoxy-Z-[p-(2', 5-dihydroxyphenethyl)phenylazo]-1 naphthol, 2,5 bisacetoxy-phenethylaniline prepared according to the citation noted in Example 1 is diazotized, coupled into 4-hydroxyethoxy-l-naphthol (prepared according to the procedure disclosed in the copending US. application of Elkan R. Blout and Milton Green, Ser. No. 683,211, filed Sept. 11, 1957), and subjected to alkali hydrolysis. 1.3 g. of the product 2-[p-(2,5-dihydroxyphenethyl) phenylazo] 4- hydroxyethoxy-l-naphthol are dissolved in 30 cc. of anhydrous pyridine and 2.3 g. (.009 mol) of butoxyethoxyethoxalyl chloride are added to the solution. The mixture is warmed in vacuo on a steam bath for 4 hours and let stand at room temperature for approximately 12 hours. The solution is then mixed with a dilute hydrochloric acid solution and the resulting slurry (filtered. The filter cake, exhibiting the consistency of a gum, is dried by repeated concentration from a benzene slurry under vacuum. The resultant residual oil is washed by slurry with benzene and dissolved in 10 cc. of chloroform. The chloroform solution is chilled to 40 C. and clarified with Celite. The clarified solution is concentrated to dryness and the resultant gum redissolved in 5 cc. of chloroform. The clarification procedure is repeated and the desired product obtained by evaporation of the chloroform solution to dryness.

EXAMPLE 5 To prepare 4-[p (2',5' dihydroxyphenethyl) phenylazo]-3 [N (,6 octaoxalyloxyethyl) carboxamido] 1- phenyl-S-pyrazolone, 2 g. of 4-[p-(2,5 dihydroxyphenethyl)-phenylazo1-3-[N (B hy-droxyethyl) carboxamido]-1-phenyl-5-pyrazolone, prepared according to the procedure disclosed in Example 1, are dissolved in 50 cc. of anhydrous pyridine. 2.2 g. of octaoxalyl chloride are added to the solution. The mixture is warmed in vacuo on a steam bath for 2 hours and let stand at room temperature for approximately 12 hours. The solution is then mixed with a dilute hydrochloric acid solution and the resulting slurry filtered. The filter cake is purified by extraction with an acetic-acid/ethyl-acetate mixture. The extract is concentrated to dryness and washed several times with a benzene-hexane mixture.

EXAMPLE 6 Percent Sodium carboxymethyl cellulose 4.5 1-phenyl-3-pyrazolidone 0.2 Sodium hydroxide 2.5 Potassium bromide 0.2

between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetate-coated baryta paper which has been coated with a solution comprising 10% N-methoxymethyl polyhexamethylene adipamide in aqueous ethanol. After an imbibition period of approximately 1 minute, the image-receiving element is separated and contains a yellow positive dye image of the photographed subject.

EXAMPLE 7 A photosensitive element is prepared by coating a gelatin-coated film base with a solution containing 4% of 4-[p-(2,5-dihydroxyphenethyl)-phenylazo]-3-[N-(fl octaoxalyloxyethyl)-carboxamido]-1-phenyl 5 pyrazolone (Formula I as prepared in Example 5), in a 4% solution of cellulose acetate hydrogen phthalate in a 50:5 0 mixture, by volume, of acetone and tetrahydrofuran. After this coating has dried, a silver iodobromide emulsion is applied. This photosensitive element is exposed and processed by spreading an aqueous liquid processing composition comprising:

Percent Sodium carboxymethyl cellulose 4.5 1-phenyl-3-pyrazolidone 0.2 Sodium hydroxide 1.5 Potassium bromide 0.2

between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetate-coated baryta paper which has been coated with a solution comprising N-methoxymethyl polyhexamethylene adipamide in 80% aqueous ethanol. After an imbition period of approximately 1 minute, the imagereceiving element is separated and contains a yellow positive dye image of the photographed subject.

EXAMPLE 8 Percent Sodium carboxymethyl cellulose 5.0 1-phenyl-3-pyrazolidone 0.6 Sodium hydroxide 3.0 6-nitrobenzimidazole 0.009

between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetate-coated baryta paper which has been coated with a solution comprising 10% N-methoxymethyl polyhexamethylene adipamide in 80% aqueous ethanol. After an imbition period of approximately 1 minute, the imagereceiving element is separated and contains a yellow positive dye image of the photographed subject.

EXAMPLE 9 A photosensitive element is prepared by coating a gelatin-coated film base with a solution containing 4% of 4- butoxyethoxyethoxalyloxyethoxy-2- [p (2',5' dihydroxyphenethyl)-phenylazo]-1-napht5hol (Formula G as prepared in Example 4), in a 4% solution of cellulose acetate hydrogen phthalate in a 50:50 mixture, by volume, of acetone and tetrahydrofuran. After this coating has dried, a silver iodobromide emulsion is applied. This photosensitive element is exposed and processed by spreading an aqueous liquid processing composition comprising:

Percent Sodium carboxymethyl cellulose 5.0 l-phenyl-3-pyrazolidone 0.8 Sodium hydroxide 3.0 G-nitrobenzimidazole 0.12 2,5-bis-ethyleneiminohydroquinone 0.6

between said photosensitive element and an image-receiving element as said elements are brought into superposed relationship. The image-receiving element comprises a cellulose acetate-coated baryta paper which has been coated with a solution comprising 10% N-methoxymethyl polyhexamethylene adipamide in 80% aqueous ethanol. After an imbibition period of approximately 1 minute, the image-receiving element is separated and contains a magenta positive dye image of the photographed subject.

It is particularly dseirable to employ a dye developer which, when hydrolyzed, exhibits an increase in its rate of transfer. Thus the present invention permits the utilization of dye developers whose rate of difliusion might be too rapid to permit eflective control if utilized initially in the free or hydrolyzed state.

Although hydrolysis may initiate immediately, the rate of hydrolysis preferably is less than the rate of development. The rate of hydrolysis, in the preferred embodi- 18 ment, thus should exhibit a lag behind the rate of development.

In all embodiments of the present invention where the developing function is available for reaction prior to hydrolysis, the rate of hydrolysis, in unexposed areas of the photosensitive element, will be high is comparison to the rate of hydrolysis in exposed areas due to the fact that hydrolyzable dye developer in the unexposed areas is in a reduced form and is thus substantially soluble and hydrolyzable. In exposed areas of the photosensitive element the dye developer, oxidized as a result of development, is during the process in a substantially insoluble form and thus a non-hydrolyzable state. The failure of the [hydrolyzable dye developer to hydrolyze in exposed areas senves to enhance the immobilization of oxidized dye developer in exposed areas of the photosensitive element.

In certain instances, the sensitivity of an associated silver halide emulsion may be affected by a reaction between the associated dye developer and a sensitizer employed in said silver halide emulsion, or by means of a displacement of sensitizing dye absorbed on the silver halide, resulting in decreased sensitivity. It has been found that the employment of the hydrolyzable dye d'evelopers of the present invention as precursors to the ultimately desired dye developers offers a means of restricting the mobility of the respective dye developers and of thus avoiding or reducing such desensitizing side reactions as might otherwise occur during storage of the photosensitive product.

a It will be noted that the liquid processing composition may, and in the above examples does, contain at least one auxiliary developer, such as p-methylaminophenol [Metol], 2,4-diaminopheno1 [Amidol], benzylaminophenol, or a 3-pyrazolidone, such as l-phenyl-S-pyrazolidone [Phenidone]. The preferred auxiliary developer is 1-phenyl-3-pyrazolidone. This auxiliary developer serves to accelerate and possibly initiate the action of the dye developer. A portion of the dye developer may be oxidized by an energy transfer reaction with oxidized auxiliary developer.

The compounds of this invention may he used also in conventional photographic processes, such as tray or tank development of conventional photosensitive films, plates or papers containing said compounds to obtain black-and white, monochromatic or toned prints or negatives. By the way of example, a processing composition suitable for such use may comprise an aqueous solution of approximately 1% sodium hydroxide, 2% sodium sulfite and 0.05% potassium bromide. After development is completed, any unreacted dye developer is washed out of the photosensitive element, preferably with an alkaline washing medium or other medium in which the unreacted dye developer is soluble. The expression toned is used to designate photographic images wherein the silver is retained with the precipitated dye, whereas monochromatic is intended to designate dye images free of silver.

It should be noted that the compounds of this invention are self-sutficient to provide the desired color image and do not depend upon coupling reactions to produce the desired color. They thus provide a complete departure from conventional photographic color processes in which the color is produced by a coupling reaction involving the oxidized developing agent.

It should be noted that it is within the scope of this invention to use mixtures of the compounds to obtain a desired color.

It will be apparent that, by appropriate selection of the image receiving elementf rom among suitable known opaque and transparent materials, it is possible to obtain either a colored positive reflection print or a colored positive transparency. Likewise, the inventive concepts herein set forth are adaptable for multicolor work by the use of special photographic materials, for example, film materials of the type containing two or more photosensitized elements associated with an appropriate number of image-receiving elements and adapted to be treated with one or moreliquid processing compositions, appropriate dye developer hydrolyzable derivatives suitable to impart the desired subtractive colors being incorporated in the 'photosensitized elements. Examples of such photographic materials are disclosed in US. Patent No. 2,647,- 049 to Edwin H. Land. I The inventive concepts herein set forth are also adapt able for the formation of colored images in accordance with the photographic products and processes described and claimed in the copending application of Edwin H. Land, Ser. No. 448,441, filed Aug. 9, 1954, and now US. Patent No. 2,968,554, and also the copending application of Edwin H. Land and Howard G. Rogers, Ser. No. 565,135, filed Feb. 13, 1956.

\In the preceding portions of the specification the expression color has been frequently used. This expression is intended to include the use of a plurality of colors to obtain black, as wel as-the use of a single black dye developer precursor.

What is claimed:

1. A dye selected from the group consisting of azo and anthraquinone dyes represented by the formula:

. o [A]LD[RO- (OR )n' o 'R ]m wherein: R is a lower alkylene group; R is an alkylene group of two to four carbon atoms; R is selected from the group consisting of phenyl or alkyl groups having from 1 to 12 carbon atoms; D is selected from the group consisting of azo and anthraquinone dye radicals; A is selected from the group consisting of ortho and paradihydroxyphenyl groups; n is 0 to 3; m is 1 or 2; and L is 1 or 2.

2. A dye as defined in claim 1, wherein said dye is 4 [p (2',5' dihydroxyphenethyl)-phenylazo]-3-[N- (,3 hexoalyloxyethyl)-carboxamido] 1 phenyl-S-pyrazolone.

3. A dye as defined in claim 1, wherein said dye is 4 [p (2',5' dihydroxyphenethyl)-phenylazo]-3-[N- (B-lauroalyloxyethyl)-carboxamido] 1 phenyl-S-pyrazolone.

4. A dye as defined in claim 1, wherein said dye is 3- [N (butoxyethoxyethoxalyloxyethyl)-carboxamido 4- [p (2',5 dihydroxyphenethyl)-phenylazo] 1 phenyl- 5-pyrazolone.

5. A dye as defined in claim 1, wherein said dye is 4 (butoxyethoxyethoxalyloxyethoxy) 2 [p-(2',5'-dihydroxyphenethyl) -phenylazo] -1-naphthol.

6. A dye as defined in claim 1, wherein said dye is 4 [p-(2',5' dihydroxyphenethyl)-phenylazo] 3 [N- (B-octaoxalyloxyethyl)-carb0xarnid0] 1 phenyl 5 pyrazolone.

No references cited.

FLOYD D. HIGEL, Primary Examiner.

US. Cl. X.R. 

